Pillar Boxed Output

Hi folks!

I am having some issues with my output being pillar boxed, to use the technical term I learned yesterday.

I captured some footage with my iPhone, put it onto my laptop and edited it in Adobe Premier Pro. I got it how I wanted it, and went to export the media. After exporting the media, the output I received had these ugly black pillars at each side of the footage.

The original footage plays just fine in full screen, but once it's been through Adobe Premier Pro, the pillar boxing issue arises.

I also use Vegas, but your problem intrigued me.
Your video is exported as 1080 x 1920 ie 1080 wide by 1920 tall.

So, I set up a project with those settings and exported using those settings in Vegas - resultant video is 1080x1920 as expected.

And when i show it it looks exavt;y like yours - black bars either side.

But - and this is the important bit - the black bars are NOT in the video. The fact is Windows Media Player (or whatever it's called in Windows 10) defaults to displaying everything in a 16:9 ratio screen. So it is that which is adding the black bars. I don't know if there is any way to force WMP to scale to fit the aspect ratio of the media, but you can do it manually by going out of full screen mode and dragging the sides.